Sex in eukaryotes

Sex predominates in eukaryotes, despite
its short-term disadvantage when compared to asexuality. Myriad models
have suggested that short-term advantages of sex may be sufficient to
counterbalance its twofold costs. However, despite decades of
experimental work seeking evidence of such short-term advantages, no
evolutionary mechanism has yet achieved broad recognition as
explanation for the maintenance of sex.

We explore here,
through lineage-selection models, the conditions favouring the
maintenance of sex.

We simulated the
mechanisms underlying the higher extinction rates of asexual lineages
than of their sexual counterparts. We linked extinction rates to the
ecological and/or genetic features of lineages, thereby providing the
first formalisation of the only figure included in Darwin’s “The origin
of species”.

Our results indicate that the long-term
advantages of sex and lineage selection may provide the most
satisfactory explanations for the maintenance of sex in eukaryotes.
Short-term benefits may play a role, but it is also
essential to take into account the selection of lineages for a thorough
understanding of the maintenance of sex.

This web site

You can find here the source code and
result examples of the second
model we proposed in the paper. This model is inspired from Darwin's
diagram and is explained in details in the associated paper.

Using the "Browser", you can select a set of parameters and visualize the trees generated with the model.

Alternatively, the C source code of the model is available under the GNU general public licence in the "Downloads" section.